Effect of N- and C-Terminal Modifications on Cytotoxic Properties of Antimicrobial Peptide Tachyplesin I

Abstract

We analyze the effects of N-terminal acetylation and C-terminal amidation on the cytotoxic properties of β-hairpin antimicrobial peptide tachyplesin I. MTT-assay showed that modified tachyplesin I exhibited increased cytotoxicity toward both tumor and normal human cells. Hemolytic activity of modified tachyplesin I was also higher than that of the initial molecule. In contrast to non-modified tachyplesin I, the peptide with C- and N-terminal modifications is resistant to proteolytic degradation in fresh human serum. C- and N-terminal modifications make tachyplesin I more attractive prototype of anticancer drug due to its more potent cytotoxic effect and better pharmacokinetic properties.

Keywords: antimicrobial peptides; chemical modification; cytotoxicity; tachyplesin I.